Motorcycle Repair/Surging Issue


QUESTION: I have a 2012 Heritage FLSTC. I did a Stage 1 with Hyperchager Pro R air filter, Bassani 2 into 1 Road Rage Exhaust, & Cobra Pro Auto tuner. Bike runs fantastic, however on smooth slow acceleration, to increase speed up from 60mph to 65/70mph I can feel a slight surging but can not hear it in the exhaust. When you ease off the throttle it goes away. If you accelerate fairly hard it doesn't do it. Shop has said it could be the air filter, the oxygen sensor or bad tuner. I placed duct tape on front half of air filter to reduce air intake from the butterflies,but that did not help. My buddy has a 2013 FLSTC with same stage 1, except he went with Rush Dual Exhaust,and we are both having the same issue. Only his is much more surge than mine. The mechanic contacted Cobra and they had him do some adjustments to the Tuner which did not help. They implied that they have had this issue before, but are giving the run around. Any input or help would be greatly appreciated. Thanks

ANSWER: What tuner is your buddy using?

---------- FOLLOW-UP ----------

QUESTION: Same tuner "Cobra Pro Auto Tuner"

Since both of you are having the same issue and both have the same tuner, I would say the problem is the programing with the tuner. I have never used this tuner, I write custom maps for Harleys, so I am not familiar with it. About the only thing you can do is either keep bugging Cobra or go with a different tuner.
Sorry I couldn't be more help

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Mike Wells


PLEASE READ BEFORE ASKING A QUESTION!!! I CAN ONLY ANSWER QUESTIONS ABOUT HARLEYS !!! I DONT KNOW ANYTHING ABOUT OTHER MODELS!!! IF YOU ASK A QUESTION ABOUT A NON HARLEY BIKE IT WILL GET REJECTED!!!I have a Harley only shop with 30 years experience located in Ohio. We specialize in complete and total repair, restoration, hi-performance, and custom bike building. I can work on Flat Heads to Twin Cams. Please, dont ask how much somthing is going to cost to fix. Labor prices differ all over te country as well as shop to shop!


If its broke on a harley we can repair it. We do complete restoration from the frame up, engine and trans rebuilding, remapping and custom bike building

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